Saturday, December 3, 2016

Hello, dear readers. It's been...a while. I promise the blog is not dead, just sleeping for now. My 2017 New Year's resolutions include sculpting specific time out for all the sci-writing goodness. Stay tuned.

Enough maudlin overtures. Now, on to the fun!

Strem has, as any synthetic guru would attest, the highest-quality metal precursors in the biz.* Now, you could spend a weekend cracking ampoules to find out, or just open to the Supporting Information of one of Jeff Bode's recent publications in Org. Lett. Perhaps you remember this reaction - SnAP synthesis of saturated heterocycles - best from a cheeky Derek Lowe tweet:

That's in reference to the stoichiometric incorporation of tin** in the reagent, which serves as a linchpin for the eventual transmetalation to a copper species and ring closure, neatly without disturbance of the ipso heteroatomic group.

Well, much to my surprise, Prof. Bode has climbed on the recent trend of showing one's work through tactful inclusion of smartphone pics to buoy up procedure adoption. Especially with fussy transition metals, valency, contaminants, poor environment, and a whole host of other factors lead to catalyst poisoning and color changes. In the SnAP case, the litmus test seems to be formation of a correctly ligated Cu(II) ion in lutidine relative to the (probable) hexaaquo cuprate species formed as a blue heterogeneous train wreck.

The kicker? The fairly indiscreet preference for the Strem copper(II) precursor over all other suppliers. Look at the change! Night and day, and key to making these reactions work.

See Arr Oh

Who is this masked chemist?

Finding my way through new challenges.
I was a founding blogger at Scientific American's Food Matters and Blog Syn. I once wrote for C&EN's The Haystack. I've written for Nature Chemistry, Newscripts, Chemistry Blog, Chemjobber, and Totally Synthetic.